The present invention relates to an information-outputting apparatus such as a monitor apparatus connected to a network connected to a plurality of electronic apparatuses through digital buses each conforming to typically the IEEE 1394 standard, an information-reporting method for informing the user of information on a content to be output by the information-outputting apparatus and an information-signal-supply-route-selecting method in the network.
In recent years, a variety of digital contents are abundantly provided by way of communication media such as broadcasting media and the Internet as well as through recording media such as a DVD (digital video disc). It is conceivably possible to widen the range of applications of such abundantly available digital contents and to well provide an environment of utilizing digital contents wherein the user has a high degree of freedom to use the contents.
It is also conceivably possible to provide a digital interface to each of a variety of digital apparatuses such as digital-content playback and recording apparatuses. By providing a digital interface to each of a variety of digital apparatuses as such, a digital content can be transmitted at a high speed and copied as well as played back without degrading the quality.
While there are a variety of digital interfaces, a digital interface conforming to the IEEE 1394 standard draws much attention. The IEEE 1394 digital interface is capable of transmitting a digital content at a high speed and protecting a copyright of a digital content with a high degree of reliability. To be more specific, the digital interface conforming to the IEEE 1394 standard is capable of transmitting signals such as digital video and audio signals, which must satisfy real-time requirements.
In addition, in a communication through a digital interface conforming to the IEEE 1394 standard between an electronic apparatus serving of a source of a digital content and an electronic apparatus serving as a recipient of the digital content, by adding information on copy control to the digital content, the apparatus transmitting the digital content is capable of determining whether or not to give the recipient apparatus a right to copy the digital content.
The electronic apparatus serving of a source of a digital content encrypts the digital content to be transmitted. If the electronic apparatus serving as a recipient of a digital content is treated as an apparatus not allowed to copy the digital content by adding information on copy control to the digital content, the recipient apparatus is not informed of an encryption key information for decrypting the encrypted digital content so that a copyright of the digital content can be protected with a high degree of reliability.
By the way, digital television broadcasting presenting digital contents through broadcasting media is already under way. It is thus conceivably possible to provide a digital monitor apparatus or a digital television receiver that has a function for receiving a digital television broadcast. In the digital television broadcasting, digital data is typically data comprising a plurality of broadcasted programs. Prior to broadcasting, the data is subjected to compression adopting an MPEG method and multiplexing. Thus, the digital monitor apparatus must have an MPEG decoder.
By providing a digital interface to a digital monitor apparatus having an MPEG decoder, a digital content completing an encoding process adopting the MPEG method can be supplied to the apparatus as it is. The digital monitor apparatus is capable of decoding and playing back the digital content. Thus, a digital interface provided to a digital monitor apparatus is conceivable.
By merely providing a digital monitor apparatus with a digital interface, however, a problem arises in some cases. That is to say, while a digital monitor apparatus having a digital interface can be connected to a digital VTR, a hard-disc drive and the so-called camcoder, which is equipment comprising a video camera and a VTR built into a single body, a video signal stored in a recording medium such as a video tape by a digital VTR or a camcoder is in some cases a DV (Digital Video) signal obtained as a result of data compression based on a DV method instead of a signal encoded by adopting the MPEG method.
The DV method is a home digital VTR standard set by an HD Digital Conference, which was established by such as manufacturers of digital equipment as promoters. In accordance with the DV method, a DV signal is obtained as a result of compressing data of a video signal in frame units. That is to say, a DV signal consists of only I (Intra) picture components in the so-called MPEG method. An I picture is a picture obtained as a result of a intra-frame encoding process.
Thus, a digital monitor apparatus having only an MPEG decoder is not capable of decoding and playing back a DV signal supplied thereto by a digital VTR or the so-called camcoder by way of the digital interface.
Assuming that a digital monitor apparatus 1 having an analog input terminal in addition to an MPEG decoder and a digital interface is connected to a DV storage 2 of typically a digital VTR, an MPEG-TS (Transport Stream) storage 3 of typically a hard disc and a DV camcoder 4 as shown in FIG. 1.
In FIG. 1, solid lines 5, 6 and 7 each represent a digital signal cable whereas dashed lines 8, 9 and 10 each represent an analog signal cable. That is to say, the digital monitor apparatus 1 is connected to the DV storage 2, the MPEG-TS storage 3 and the DV camcoder 4 by the analog signal cables 8, 9 and 10 respectively and to the DV storage 2 by the digital signal cable 5, whereas the DV storage 2 is connected by the digital signal cable 6 to the MPEG-TS storage 3 which is connected to the DV camcoder 4 by the digital signal cable 7 to form a network.
It should be noted that the MPEG-TS storage 3 is an apparatus used for, among others, storing and playing back an MPEG-TS signal, which is obtained as a result of a process of multiplexing digital contents each resulting from data compression adopting the MPEG method.
A content decoded by the DV storage 2, the MPEG-TS storage 3 or the DV camcoder 4 into an analog signal is supplied to the digital monitor apparatus 1 through the analog signal cable 8, 9 or 10 respectively. In this case, the video of the content is displayed on a screen G of the digital monitor apparatus 1 as shown in FIG. 2A and the sound of the content is output by speakers SP1 and SP2 as is the case with the conventional apparatus.
By the same token, an MPEG-TS signal can be supplied from the MPEG-TS storage 3 to the digital monitor apparatus 1 through the digital signal cables 6 and 5 as it is. In this case, since the digital monitor apparatus 1 has an MPEG decoder, the monitor apparatus 1 is capable of displaying the video of the digital content on the screen G thereof as shown in FIG. 2A and outputting the sound of the content through the speakers SP1 and SP2.
By the same token, a DV signal can be supplied to the digital monitor apparatus 1 from the DV storage 2 through the digital signal cable 5 or from the DV camcoder 4 through the digital signal cables 7, 6 and 5 as it is. In this case, however, since the digital monitor apparatus 1 does not have a DV decoder, the monitor apparatus 1 is not capable of playing back the DV signal. As a result, as a conceivable method, the digital monitor apparatus 1 is put in a mute state as typically shown in FIG. 2B to prevent the video and the sound of the digital content from being output as noises.
With such a method, however, the user is not capable of immediately knowing why the content the user is trying to watch and listen to is not played back. In addition, in the case of a network comprising a plurality of electronic apparatuses connected to each other as shown in FIG. 1, the user of the digital monitor apparatus 1 is not capable of recognizing which route is used for supplying a content to the monitor apparatus 1 from an external apparatus connected to the monitor apparatus 1 by the network.
In the case of the network shown in FIG. 1, for example, as described above, the digital monitor apparatus 1 serving as the core apparatus may receive 3 different kinds of contents, namely:
(1) a decodable and reproducible digital content;
(2) an undecodable digital content; and
(3) a content supplied as an analog signal.
If an undecodable digital content is inadvertently supplied to the digital monitor apparatus 1, there may be raised a problem that the undecodable digital content is interpreted incorrectly as a failure occurring in the monitor apparatus 1 or the apparatus generating the content. In addition, since a content may be supplied to the digital monitor apparatus 1 from the same electronic apparatus through an analog signal cable or a digital signal cable, it is difficult to handle contents in the information reporting and outputting system in some cases. Thus, the environment for utilizing a digital content cannot be said to be sufficiently well provided yet.
The present invention presents an information-outputting apparatus, an information-reporting method and an information-signal-supply-route-selecting method, which provide a digital-content utilization environment giving the user a high degree of freedom to make use of the apparatus and the methods.
The information-outputting apparatus provided by the present invention is an apparatus connected to a network comprising a plurality of electronic apparatuses connected to each other by digital buses. The information-outputting apparatus comprises: a digital interface unit for receiving a digital signal transmitted through one of the digital buses; information-detecting means for detecting source-apparatus information indicating an electronic apparatus serving as a source outputting the digital signal and information on a format of the digital signal from the digital signal, which is received through the digital interface unit; and information-reporting means for reporting the source-apparatus information and the information on the format, which are detected by the information-detecting means.
In the information-outputting apparatus described above, source-apparatus information and information on a format, which are transmitted through a digital bus along with a main digital signal, are detected by the information-detecting means and reported by the information-reporting means.
It is thus possible for the user to know which electronic apparatus connected to a digital bus has supplied a digital signal and what format the digital signal has.
In addition, the information-outputting apparatus further has information-tabularizing means for organizing source-apparatus information and information on a format, which are detected by the information-detecting means, for each of the electronic apparatuses connected to the network in a table by associating the pair of source-apparatus information and information on a format with the corresponding electronic apparatus, whereas the information-reporting means reports the information tabularized by the information-tabularizing means to the user.
In the information-outputting apparatus, the information-detecting means detects a source-apparatus number and information on a format for each of the electronic apparatuses connected to the network. Then, the information-tabularizing means organizes the detected pieces of information into a table by associating them with the corresponding electronic apparatus. Finally, the information-reporting means reports some or all of the information tabularized by the information-tabularizing means.
It is thus possible for the information-outputting apparatus to inform the user of the information-outputting apparatus of source-apparatus information and information on a format, which are each received as an information signal along with a main digital signal, and information on connections of the other electronic apparatuses connected to the network.
Furthermore, the information-outputting apparatus described above has: one or more base-band-signal input terminals each connected to one of the electronic apparatuses connected to the network and each used for receiving a base-band signal generated by the electronic apparatus; and information-adding means for adding source-apparatus information indicating a source apparatus generating a base-band signal and information, which indicates the format of the base-band signal in case the base-band signal has been encoded, for each of the electronic apparatuses connected to the base-band-signal input terminals to the information tabularized by the information-tabularizing means by associating the source-apparatus information with the information indicating the format.
Moreover, the information-outputting apparatus has one or more base-band-signal input terminals each connected to an electronic apparatus and used for receiving a base-band signal generated by the electronic apparatus, and a source-apparatus number of a base-band signal received through each of the base-band-signal input terminals and information, which indicates the format of the base-band signal in case the base-band signal has been encoded, are added to the information tabularized by the information-tabularizing means.
It is thereby possible for the information-outputting apparatus to report information on base-band signals each received through a base-band-signal input terminal through the tabularized information as a table. Thus, the information-outputting apparatus is capable of controlling both the connection environment of digital signals and the connection environment of base-band signals.
In addition, the information-outputting apparatus described above also has apparatus-pointing means for pointing out a source apparatus generating a signal presently displayed on a screen in the tabularized information.
The information-outputting apparatus having such apparatus-pointing means allows the user to recognize a source apparatus generating a signal received by the information-outputting apparatus and presently displayed on a screen in the tabularized information. It is thus possible to report an electronic apparatus serving as a source generating a signal presently displayed on a screen and other electronic apparatuses in the network with ease and with a high degree of reliability.
The information-outputting apparatus described above further has: signal-decoding means for decoding a digital signal having a predetermined format among digital signals received by the digital interface unit; and decodable/undecodable judgment means for forming a judgment as to whether or not a digital signal received by the digital interface unit can be decoded by the signal-decoding means, wherein the information-reporting means reports the fact that a digital signal received by the digital interface unit is undecodable to the user in case an outcome of a judgment formed by the decodable/undecodable judgment means indicates that the digital signal is undecodable.
In the information-outputting apparatus described above, the information-reporting means reports the fact that a digital signal received by the digital interface unit is undecodable in case an outcome of a judgment formed by the decodable/undecodable judgment means indicates that the digital signal is undecodable.
Thus, the user of the information-outputting apparatus is capable of knowing which electronic apparatus connected to a digital bus outputs an undecodable and, hence, normally irreproducible main digital signal, as well as a format the digital signal has. Thus, when an undecodable and, hence, normally irreproducible main digital signal is supplied to the information-outputting apparatus, the user of the information-outputting apparatus will not incorrectly interpret the abnormal playback state as a failure occurring in the information-outputting apparatus. In addition, the user is allowed to carry out a manual operation to transfer the transmission route of the information signal so as to supply the main digital signal to another electronic apparatus that is capable of decoding the signal.
The decodable/undecodable judgment means employed in the information-outputting apparatus provided by the present invention forms a judgment as to whether a digital signal received by the digital interface unit is decodable or undecodable on the basis of the information on a format detected by the information-detecting means.
In the information-outputting apparatus described above, information on a format detected by the information-detecting means is used by the decodable/undecodable judgment means as a basis for forming a judgment as to whether a digital signal received by the digital interface unit is decodable or undecodable. Thus, the information-outputting apparatus is capable of forming a judgment quickly as to whether a digital signal received by the digital interface unit is decodable or undecodable without the need to make an attempt to decode the signal.
In the information-outputting apparatus, the information-reporting means reports information to the user by displaying the information on a display unit.
To be more specific, the information-reporting means displays information on source apparatuses, information on formats and the like on the display unit. It is thus possible to notify the user of the information-outputting apparatus of the information on source apparatuses, the information on formats and the like with a high degree of reliability.
In the information-outputting apparatus provided by the present invention, the information-reporting means outputs information as a sound or a voice generated by speakers.
To be more specific, the information-reporting means outputs information on source apparatuses, information on formats and the like as a sound or a voice generated by the speakers. It is thus possible to notify the user of the information-outputting apparatus of information on source apparatuses, information on formats and the like as audio information with a high degree of reliability.
In the information-outputting apparatus provided by the present invention, the information-reporting means reports information to the user by displaying the information on a display unit, and outputs information as a sound or a voice generated by the speakers.
By reporting information on source apparatuses, information on formats and the like as information displayed on a display unit, and outputting information on source apparatuses, information on formats and the like as a sound or a voice generated by the speakers, the information-outputting apparatus is capable of reporting the information on source apparatuses, the information on formats and the like with a high degree of reliability.
The information-outputting apparatus provided by the present invention further has encrypted/unencrypted judgment means for forming a judgment as to whether or not a digital signal received by the digital interface unit has been encrypted, and the information-reporting means reports a result of judgment output by the encrypted/unencrypted judgment means to the user.
In the information-outputting apparatus described above, the encrypted/unencrypted judgment means forms a judgment as to whether or not a digital signal received by the digital interface unit has been encrypted, and the information-reporting means reports a result of judgment output by the encrypted/unencrypted judgment means. Thus, when an encrypted main digital signal supplied to the information-outputting apparatus cannot be decrypted and, hence, cannot be played back normally, the user of the information-outputting apparatus will know that the main digital signal cannot be played back normally because the digital signal was encrypted so that the user will not incorrectly interpret the abnormal playback state as a failure occurring in the information-outputting apparatus.
As an implementation, in the information-outputting apparatus provided by the present invention, the information-detecting means is also capable of detecting information indicating whether or not a digital signal received by the digital interface unit has been encrypted from the digital signal; and in this case, the encrypted/unencrypted judgment means forms a judgment as to whether or not a digital signal received by the digital interface unit has been encrypted on the basis of the information detected by the information-detecting means to indicate whether or not the digital signal received by the digital interface unit has been encrypted.
As described above, in the information-outputting apparatus provided by the present invention, the information-detecting means detects information indicating whether or not a digital signal received by the digital interface unit has been encrypted from the digital signal; and the encrypted/unencrypted judgment means forms a judgment as to whether or not a digital signal received by the digital interface unit has been encrypted on the basis of the information detected by the information-detecting means to indicate whether or not the digital signal received by the digital interface unit has been encrypted.
As a result, the information-outputting apparatus is capable of determining whether or not a digital signal has been encrypted with a high degree of reliability without the need to carry out an operation such as to make an attempt to decrypt the digital signal.
In addition, the information-outputting apparatus provided by the present invention allows an electronic apparatus connected to the network to make an arbitrary access to the tabularized information.
As described above, another electronic apparatus connected to the network is capable of making an arbitrary access to the tabularized information in the information-outputting apparatus. Thus, another electronic apparatus connected to the network is capable of making use of the tabularized information in the information-outputting apparatus without the need to tabularize source information IDs and information on formats into a table in the other electronic apparatus itself.
In addition, another information-outputting apparatus provided by the present invention is also an apparatus connected to a network comprising a plurality of electronic apparatuses connected to each other by digital buses. The information-outputting apparatus comprises: one or more base-band-signal input terminals each connected to an electronic apparatus and used for receiving a base-band signal generated by the electronic apparatus; a digital interface unit for receiving a digital signal transmitted through one of the digital buses; decodable/undecodable judgment means for forming a judgment as to whether or not a digital signal received by the digital interface unit can be decoded by the information-outputting apparatus; and input-signal-switching means for switching a signal input so as to receive a base-band signal from one of the base-band-signal input terminals when an outcome of a judgment formed by the decodable/undecodable judgment means indicates that a digital signal received by the digital interface unit cannot be decoded by the information-outputting apparatus.
As described above, in the information-outputting apparatus, the input-signal-switching means switches the signal input so as to receive a base-band signal from one of the base-band-signal input terminals when an outcome of a judgment formed by the decodable/undecodable judgment means indicates that a main digital signal received by the digital interface unit cannot be decoded by the information-outputting apparatus.
Thus, when a main digital signal received by the digital interface unit cannot be decoded by the information-outputting apparatus, the signal input can be switched automatically to receive a signal already decoded by another electronic apparatus connected to the same network from the other electronic apparatus without the need for the user to carry out a manual operation.
In addition, the information-outputting apparatus provided by the present invention further has command issuing means for issuing a command to an electronic apparatus, which is connected to the network and capable of decoding a digital signal, to decode the digital signal and output the decoded digital signal as a base-band signal in the case of an outcome of a judgment formed by the decodable/undecodable judgment means indicating that the same digital signal received by the digital interface unit cannot be decoded by the information-outputting apparatus.
As described above, the command issuing means employed in the information-outputting apparatus is capable of issuing a command to an electronic apparatus, which is connected to the network and capable of decoding a digital signal undecodable by the information-outputting apparatus, to decode the digital signal and output the decoded digital signal as a base-band signal. Thus, it is possible to decode a desired digital signal with a high degree of reliability and to use the decoded signal without the need for the user to carry out a manual operation.
The digital buses employed in the information-outputting apparatus provided by the present invention are each a bus conforming to the IEEE 1394 standard.
As described above, the information-outputting apparatus employs buses each conforming to the IEEE 1394 standard as the digital buses. Thus, digital information signals required to satisfy a real-time condition such as digital video and audio signals can be transmitted at a high speed and the copyright of the digital information signals can be protected reliably and properly.
As described above, in accordance with the present invention, when digital data of a content undecodable by the information-outputting apparatus is supplied to the information-outputting apparatus, information on the content can be reported to the user or another apparatus external to the information-outputting apparatus. It is thus possible to solve a problem of the user""s misinterpreting a normally irreproducible digital data due to an inability to decode the digital data as a failure occurring in an electronic apparatus in use.
In a network comprising a plurality of electronic apparatuses connected to each other by digital buses, information on digital data generated by each of the electronic apparatuses connected to the network can be tabularized into a content information table. In addition, connection status of the network comprising a plurality of electronic apparatuses connected to each other by digital buses can be reported to the user and the electronic apparatuses connected to the network.
The user can thus make use of the content information table provided by the information-outputting apparatus as a basis for selecting an optimum supply route of an electronic apparatus considered to be a source of desired digital data. It is therefore possible to improve convenience provided to the user in utilization of the network.
In addition, when digital data that cannot be decoded by the information-outputting apparatus connected to a network comprising a plurality of electronic apparatuses connected to each other by digital buses is supplied to the information-outputting apparatus, the digital data is rerouted to an electronic apparatus capable of decoding the data before re-supplying the decoded digital data to the information-outputting apparatus as a base-band signal. As a result, by rerouting undecodable digital data directly supplied to the information-outputting apparatus to an electronic apparatus capable of decoding the undecodable digital data, the digital data can be used.
Moreover, by using digital buses, it is also possible to construct a network covering all electronic apparatuses and providing the user with convenience and a high degree of freedom to use.